The present invention relates generally to the field of orthopedic medicine and more specifically to the design of an improved medical bandage cover or padding, a medical bandage formed of a moisture-curable material, particularly a splint, and a medical bandaging product, each having an improved cover or padding as disclosed in this application.
Medical bandages for use in the treatment of injuries, such as broken bones requiring immobilization of a body member, historically have been formed from a strip of fabric or scrim material impregnated with a substance which hardens into a rigid structure after the strip has been wrapped around the body member. The hardening substance traditionally used in carrying out this procedure is plaster-of-paris, and much plaster-of-paris splint material is still sold throughout the world, including by the present applicant.
The above-described application procedure can be messy and time-consuming. Several components are required and considerable skill is necessary. The hardened material is subject to deterioration during wear, and can cause odor and itching. For these reasons, two or more splints or casts may be required during a single injury recovery period.
In order to alleviate the above-recited disadvantages of the conventional application procedure for plaster-of-paris casts and splints, unitary splinting materials have been devised and are disclosed in, for example, U.S. Pat. Nos. 3,900,024, 3,923,049, and 4,235,228. All of these patents describe a splint material substrate with a plurality of layers of plaster-of-paris impregnated cloth. Such unitary splinting materials are not as messy and can be applied more quickly, but still suffer from a number of disadvantages inherent in plaster-of-paris cast materials. All plaster-of-paris splints have a relatively low strength to weight ratio that results in a finished splint that is heavy and bulky. Plaster-of-paris splints are slow to harden, requiring 24 to 72 hours to reach maximum strength. Since plaster-of-paris breaks down in water, bathing and showering are difficult.
An advance in the art of casting and splinting is disclosed in U.S. Pat. Nos. 4,411,262 and 4,502,479. The casting materials disclosed in these patents comprise a flexible fabric impregnated with a moisture-curable resin enclosed in a moisture-free, moisture-impervious package. Compared to plaster-of-paris, these products are lightweight, have a very high strength to weight ratio and can be made relatively porous, permitting a flow of at least some air through the splinting material to the skin. Early prior art moisture-curing systems included a package within which was contained a “pre-cut” bandage having a plurality of layers of fabric, such as fiberglass, impregnated with the moisture-curing resin. No provision is made in these “pre-cut” bandages for re-closing the package, so that the entire material must be very quickly used after removal from the package since such moisture-curing resins will cure in a relatively short period of time due to contact even with only atmospheric moisture. In many cases, substantial wastage is created when the desired size or shape is not in inventory, and larger sizes are cut down to the required size and shape, and the remaining material discarded.
Further significant developments in the splinting area are disclosed in U.S. Pat. Nos. 4,770,299; 4,869,046; 4899738 and 5,003,970, owned by present applicant. Each of these patents discloses various roll-form, moisture-curable splint products that permit predetermined lengths of a medical bandage to be severed from a roll for use, while the remaining medical bandage is maintained in a soft, moisture-proof condition until ready for later use. These applications disclose the use of multiple layers of fiberglass fabric positioned in a synthetic, non-woven fabric protective layer, in other words, a outer cover, for residing between the hardened substrate and the patient.
The present invention relates more particularly to the cover that encloses the hardened splint substrate. The cover as disclosed in this application is a water-resistant, breathable fabric cover, and the preferred fabric is a knitted spacer fabric. The term “cover” is used in this application to include materials that are sufficiently thick to provide a padded or cushioning type of protection, as well as thinner materials that offer separation between the wearer's skin and the hardened substrate, without necessarily being thick enough to be characterized as “padding” or “cushioning material.” The cover is applied to the surface of the hardened splint material on at least the side to be placed next to the skin in order to offer protection to the skin of the patient.
The knitted orthopedic cover according to the invention disclosed in this application is water resistant and therefore allows the patient to bathe, shower or swim without the concerns of getting the splint wet. The water-resistant cover is constructed in such a way as to allow maximum air movement around the injury site, making the splint more comfortable to wear. The skin of the patent is kept in a cool, low moisture environment that promotes healing while helping to prevent skin irritation and itching.
Current splint padding materials are usually constructed of non-woven synthetic fibers that are typically very dense in structure and therefore difficult to dry because of poor breathability and porosity.
Splints are often required to reside against the surface of the skin for long periods of time and can thus cause problems such as maceration of the skin. The high fiber density of known paddings and covers also keeps moisture trapped in the material which can cause bacteria to multiply to an undesirable degree.
The non-woven orthopedic padding currently used in the medical field will, when in contact with the skin of the patient, absorb into its fibrous structure perspiration and other body fluids even though the fibers themselves are hydrophobic. This absorption causes the non-woven splint padding to reduce in thickness and compact into an even denser structure. This compaction and reduction in thickness has a detrimental effect on the comfort of the padding when in contact with the skin of the patient.
To overcome these and other problems associated with the use of orthopedic non-woven splint padding, this application discloses and claims a water-resistant orthopedic splint cover material. The preferred embodiment of this water-resistant orthopedic splint cover is based on a knitted spacer fabric using a combination of monofilament and multifilament yarns.
The invention described in this application thus provides a orthopedic splint cover or padding material that is optimized for use with moisture-curing synthetic splints, and enhances the advantages provided by this type of splinting system. One such unitary system uses a knitted spacer padding placed around and encircling a substrate having moisture-curing resin applied thereto, together with a moisture-impervious package with means for resealing the package against entry of moisture after a desired length of bandaging product has been removed for use.
Another preferred embodiment of the cover and padding according to the invention permits the provision of pre-cut lengths of splint sealed against moisture intrusion until use.